They also mention the creator of this site: http://www.geocities.jp/tengaimakyouzero/tengaizero.html
Tons of info about Tengai Makyou Zero on that one.It's in Japanese but they said it helped them a lot during the project.Patch is working fine on real carts and bsnes emulator.Game looks great,now we can understand what's going on with the story.Kudos to all involved in the translation!

P.S.: Ok,i know it's not a PC Engine game but it's Tengai Makyou,it's Hudson! It has many things in common with the first 2 PC Engine games,i hope this translation inspires someone in the future to release their own patches for Ziria,Manjimaru and other Tengai Makyou games.